Enhanced Alamouti Decoding Scheme for DVB-T2 Systems in SFN Channels

The standard Alamouti space-frequency block code (SFBC) suffers from performance degradation when used over highly frequency-selective channels because the channel frequency response is not necessarily flat over the Alamouti block. In this paper, we present an enhanced Alamouti space frequency block decoding scheme for multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems over highly frequency selective channels. The enhanced Alamouti scheme uses the channel frequency variations in consecutive subcarriers to adapt the Alamouti decoder. Simulation results of DVB-T2 system confirm that the proposed method has substantial performance improvement in terms of bit error rate when compared to standard Alamouti decoder mainly over highly frequency-selective channels such as single frequency networks (SFN).